The Return key in this custom keyboard allows user to add new lines in the popular WeChat application. In addition, this soft keyboard also support Cut, Copy, Paste, Left and Right direction keys.
In order to use this custom keyboard, you need to first go to Settings->General->Keyboards page, and then select "Keyboards"->"Add New Keyboard..." to add "NewLine" keyboard. After the "NewLine" keyboard item shows in Keyboard list, click it and then enable "Allow Full Access".
Delete this application from your iPhone will also delete the NewLine custom keyboard from your device.